toxin

tox·in

any of various poisonous compounds produced by some microorganisms and causing certain diseases

any of various similar poisons, related to proteins, formed in certain plants, as ricin, or secreted by certain animals, as snake venom: toxins, when injected into animals or humans, typically initiate the formation of antitoxins

Origin of toxin

tox(ic) + -in

toxin

noun

A poisonous substance, especially a protein, that is produced by living cells or organisms and is capable of causing disease when introduced into the body tissues but is often also capable of inducing neutralizing antibodies or antitoxins.

A poisonous or harmful nonbiological substance, such as a pollutant.

toxin

Noun

(plural toxins)

A toxic or poisonous substance produced by the biological processes of biological organisms.